Delay is the leading challenge in completing Engineering, Procurement, and Construction (EPC) projects. Delay can cause excess costs, which reduces company profits. The relationship between subcontractors and the main contractor is a critical factor that can support the success of an EPC project. The problematic financial condition of the main contractor can cause delay in payments to subcontractors. This research will set a model that combines the system dynamics and earned value method to describe the impact of subcontractor advance payments on project performance. The system dynamics method is used to model and analyze the impact of interactions between variables affecting project performance, while the earned value method is applied to quantitatively evaluate project performance and forecast schedule and cost outcomes. These two methods are used complementarily to achieve a holistic understanding of project dynamics and to optimize decision-making. The designed model selects the optimum scenario for project time and costs. The developed model comprises project performance, costs, cash flow, and performance forecasting sub-models. The novelty in this research is a new model for optimizing project implementation time and costs, adding payment rate variables to subcontractors and subcontractor performance rates. The designed model can provide additional information to assist project managers in making decisions.

Attempts were made in the present study to design and develop skeletally modified ether linked tetraglycidyl epoxy resin (TGBAPSB), which is subsequently reinforced with different weight percentages of amine functionalized mullite fiber (F-MF). The F-MF was synthesized by reacting mullite fiber with 3-aminopropyltriethoxysilane (APTES) as coupling agent and the F-MF structure was confirmed by FT-IR. TGBAPSB reinforced with F-MF formulation was cured with 4,4’-diamino diphenyl methane (DDM) to obtain nanocomposite. The surface morphology of TGBAPSB-F-MF epoxy nanocomposites was investigated by XRD, SEM and AFM studies. From the study, it follows that these nanocomposite materials offer enhancement in mechanical, thermal, thermo-mechanical, dielectric properties compared to neat (TGBAPSB) epoxy matrix. Hence we recommend these nanocomposites for a possible use in advanced engineering applications that require both toughness and stiffness.

This paper describes the significance, content, progress and corresponding basic theory and experimental research methods of micron/nanometer scale thermal science and engineering, which is one of the latest cutting-edge disciplines, and analyzes the effects of micron nanometer devices on the scale effect series of challenging hot issues, discussed the corresponding emergence of some new phenomena and new concepts, pointed out that the micron/nano thermal science aspects of the recent development of several types of theory and experimental technology success and shortcomings, and summed up a number for the exploration of the new ways and new directions, especially on some typical micron/nano-thermal devices and micro-scale biological heat transfer in some important scientific issues and their engineering applications were introduced.

The developmental and advancement of engineering vis-à-vis scientific and technological research and development (R&D) has contributed immensely to sustainable development (SD) initiatives, but our future survival and development are hampered by this developmental and advancement mechanism. The threat posed by current engineering vis-à-vis scientific and technological practices is obvious, calling for a paradigm change that ensures engineering as well as scientific and technological practices are focused on SD initiatives. In order to promote sound practices that result in SD across all economic sectors, it is currently necessary to concentrate on ongoing sustainable engineering vis-à-vis scientific and technological education. Hence, this perspective review article will attempt to provide insight from Sub-Saharan Africa (Nigeria to be specific) about how engineering vis-à-vis scientific and technological R&D should incorporate green technologies in order to ensure sustainability in the creation of innovations and practices and to promote SD and a green economy. Furthermore, the study highlights the importance as well as prospects and advancements of engineering vis-à-vis scientific and technological education from the in Sub-Saharan Africa context.

This review comprehensively summarizes various preparatory methods of polymeric bone scaffolds using conventional and modern advanced methods. Compilations of the various fabrication techniques, specific composition, and the corresponding properties obtained under clearly identified conditions are presented in the commercial formulations of bone scaffolds in current orthopedic use. The gaps and unresolved questions in the existing database, efforts that should be made to address these issues, and research directions are also covered. Polymers are unique synthetic materials primarily used for bone and scaffold applications. Bone scaffolds based on acrylic polymers have been widely used in orthopedic surgery for years. Polymethyl methacrylate (PMMA) is especially known for its widespread applications in bone repair and dental fields. In addition, the PMMA polymers are suitable for carrying antibiotics and for their sustainable release at the site of infection.